Substance misuse, psychiatric disorder and violent and disturbed behaviour

Background Epidemiological studies suggest schizophrenia and substance misu se to be associated with a higher rate of violence and crime. Aims The literature was evaluated to assess whether people with schizophren ia who use substances have an increased risk for violence and disturbed beh aviour. Method A detailed Medline analysis was performed and relevant studies were reviewed. Results A large number of studies have linked substance misuse in schizophr enia with male gender, high incidence of homelessness, more pronounced psyc hotic symptoms, non-adherence with medication, poor prognosis, violence and aggression The latter has been proved by clinical, epidemiological and lon gitudinal prospective studies of unselected birth cohorts. The increased ri sk for aggression and violent acts cannot be interpreted only as a result o f poor social integration. Male gender, more severe psychopathology, a prim ary antisocial personality, repeated intoxications and non-adherence with t reatment are important confounding variables. Conclusion Substance misuse has been shown consistently to be a significant risk factor for violence and disturbed behaviour. Future research should t ry to evaluate possible pharmacological and psychosocial treatment approach es. Declaration of interest None.